A cartridge such as a process cartridge configured to form an image is known. An image forming apparatus includes a plurality of process cartridges mounted therein, wherein the plurality of process cartridges respectively store developer having different colors. Specifically, the image forming apparatus includes a tray provided to be drawable from an apparatus body in the horizontal direction. The tray includes a pair of side walls provided to oppose each other with a predetermined distance therebetween. The plurality of process cartridges are held in the tray to be parallel with each other in the horizontal direction between the pair of wails. In a state where the tray is drawn from the apparatus body, a process cartridge can be taken out by pulling up the process cartridge from the tray.
In the image forming apparatus, each of the process cartridges held in the tray opposes each of the side walls of the tray with a small distance therebetween. The process cartridge and each side wall have opposing surfaces which oppose each other, and the opposing surfaces are flat in the upper-lower direction.
Therefore, while the process cartridge is pulled up from the tray, if the posture of the process cartridge is inclined by even a small amount, there is a concern that the process cartridge is hung on the side walls of the tray, so that the pulling up operation of the process cartridge can become not smooth. Similarly, while the process cartridge is mounted in the tray from above, the same problem can occur.
In other to smoothly pull up (mount in) the process cartridge, it is conceivable to increase the distance between the process cartridge and the respective side walls of the tray. However, if the distance were increased by a large amount, the process cartridge became likely to unnecessarily rattle in a state where the process cartridge is provided between the pair of side walls. For example, in the state where the process cartridge is provided between the pair of the side walls, when a driving force or power is applied to the process cartridge from the apparatus body through each of the side walls, it is difficult to stably apply a driving force or power to the process cartridge since the process cartridge is unstable. Accordingly, the rattling of the process cartridge between the pair of side walls needs to be suppressed as much as possible.